Alright Fella's, A few questions....I have a 49 Chevy truck which i'm wanting to put a small block in, now I know changing the rear end is going to be the easiest option but.... Is there any way of mating the original chevy rear end up with a small block and 700r4 box? Also changing the gearing in the rear end to something more highway friendly? Would it be do-able? Thanks Seb
The ONLY thing I've seen/heard about, is Langdon's kit to install a Saginaw 4-speed onto a torque tube rear end. You have to send the mainshaft in to Langdon's for machine work. But, that's a manual shift setup and you want automatic. As far as the rear end gearing goes, I "think" Langdon's also has steeper gears (3.55:1 ???). Maybe find an old hydramatic for the torque tube truck, but that may be difficult where you're located. Butch/56sedandelivery.
When the Powerglide went f0o0o0ked on my 53 Chevy car i considered an engine and tranny swap but general consensus seemed to be that the torque tube & rear end would need to be swapped out too. It has the ball and socket seal at the gearbox end of the tube would need sealing somehow. In the end I found another cast iron Powerglide over here and managed. I'm not sure if this is the case for pickups though.
49 chevy, a 700r4 is a long transmission comparatively, you are already changing out most of the drive line. Finding a decent rearend and newer style drive shaft should be easy and cheap. Even if you have to get the drive shaft adjusted for length just get one thats is a bit too long and cutting it down should be cheap. Fyi- these old trucks are loud when driven at modern highway speeds! I would look at a rearend with 3.73 gears, they match well to the 700r4 and still allow some decent acceleration and torque!
I have got a rear end already just need it rebuilding it's getting 3.70 gears....got the 700r4 too. I was just wondering IF it could be done....?
Yes it CAN be done. You CAN travel from London to New York City in a row boat. Just because you can don't mean that you should. The later rear end is easier, cheaper, and yeilds a better result.
The Saginaw 4-speed mainshaft/kit and the 3:55 gears originated with Patrick Dykes, not Langdons... Really no way to do what you ask without lots of custom machine work. And the end result will probably be unsatisfactory. Good luck.
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